Eco-geographic adaptations in the human ribcage throughout a 3D geomet-ric morphometric approach.

GARCÍA MARTÍNEZ, D. ; NALLA, S.; FERREIRA, M. T.; GUICHÓN, R. A.; D'ANGELO DEL CAMPO, M. D. ; BASTIR, M.

AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY

WILEY-LISS, DIV JOHN WILEY & SONS INC

Lugar: New York; Año: 2018 vol. 2 p. 323 - 336

0002-9483

Objectives: According to eco-geographic rules, humans from high latitude areas present larger andwider trunks than their low-latitude areas counterparts. This issue has been traditionally addressedon the pelvis but information on the thorax is largely lacking. We test whether ribcages are largerin individuals inhabiting high latitudes than in those from low latitudes and explored the correlationof rib size with latitude. We also test whether a common morphological pattern is exhibited in thethorax of different cold-adapted populations, contributing to their hypothetical widening of thetrunk.Materials and methods: We used 3D geometric morphometrics to quantify rib morphology ofthree hypothetically cold-adapted populations, viz. Greenland (11 individuals), Alaskan Inuit (8 individuals) and people from Tierra del Fuego (8 individuals), in a comparative framework withEuropean (Spain, Portugal and Austria; 24 individuals) and African populations (South African andsub-Saharan African; 20 individuals).Results: Populations inhabiting high latitudes present longer ribs than individuals inhabiting areascloser to the equator, but a correlation (p< 0.05) between costal size and latitude is only found inribs 7?11. Regarding shape, the only cold adapted population that was different from the noncold-adapted populations were the Greenland Inuit, who presented ribs with less curvature andtorsion.Conclusions: Size results from the lower ribcage are consistent with the hypothesis of largertrunks in cold-adapted populations. The fact that only Greenland Inuit present a differential morphological pattern, linked to a widening of their ribcage, could be caused by differences in latitude.However, other factors such as genetic drift or specific cultural adaptations cannot be excludedand should be tested in future studies.